Locomotion

Year (first built)	1825
Wheel arrangement (Whyte)	0-4-0
Power type	Steam
Railway / Company	Stockton & Darlington Railway
Manufacturer / Builder	Robert Stephenson and Company
Designer	George Stephenson, Robert Stephenson
Boiler pressure	Approximately 3.4 bar (50 psi), Stephenson's standard low pressure of the period.
Cylinders	Twin vertical cylinders, 9½ in diameter × 24 in stroke, set partly within the boiler casing for compactness. The cylinders drove the rear coupled axle through long connecting rods.
Tractive effort	Demonstrated capability: hauling 80 tons of coal at 4 mph, or 38 wagons (approximately 200 passengers) at 8 mph, the loadings achieved on the S&DR opening day train of 27 September 1825.
Max speed	Approximately 24 km/h (15 mph) on the level, claimed during early service.
Purpose / Type	Hauling coal and passenger trains on the Stockton & Darlington Railway from the colliery feeders at Witton Park to the coal staiths at Stockton-on-Tees, the world's first public railway open to general traffic.

Locomotion was George Stephenson's 1825 locomotive, the engine that hauled the opening train of the Stockton & Darlington Railway on 27 September 1825, the world's first public railway open to general traffic. Built by Robert Stephenson and Company at Newcastle to a design by George Stephenson, Locomotion (often known retrospectively as "Locomotion No. 1") inaugurated the modern era of steam railway transport.

The design used twin vertical cylinders set into the rear of the boiler casing for compactness, driving the rear coupled axle through long connecting rods. The wheels were coupled by external rods, the direct-drive arrangement that Stephenson had been developing through his Killingworth engines Blücher (1814) and Killingworth Billy (1816). The cylindrical boiler operated at approximately 50 psi with a single internal flue.

The engine was completed in September 1825 and immediately placed in service for the line's opening on 27 September. The opening train consisted of 38 wagons, coal, goods, and temporary passenger seating, with a passenger carriage labelled "Experiment" carrying the railway directors. Stephenson himself drove Locomotion on the opening day. The 12-mile run from Shildon to Stockton-on-Tees took approximately two hours and was witnessed by an estimated 40,000 spectators.

Locomotion worked the Stockton & Darlington Railway from 1825 onwards. In April 1828 the engine suffered a boiler explosion that killed driver John Cree; it was rebuilt and returned to service. By the early 1830s the Stephenson Rocket of the Rainhill Trials had introduced the multi-tube boiler and demonstrated speeds far beyond Locomotion's capability, and Locomotion was progressively assigned to lighter work. The engine was finally retired in 1841 after 16 years' service.

The Stockton & Darlington Railway recognised the engine's historical significance and preserved it as a static exhibit at North Road station, Darlington, from 1841 onwards, one of the longest preservation periods of any historic engine. Currently Locomotion is a centrepiece exhibit at Locomotion: The National Railway Museum at Shildon, County Durham, fittingly close to its original S&DR home. A working full-size replica was built in 1975 for the 150th anniversary of the S&DR and has been operated periodically on heritage railways including Beamish.

Design and development

By 1823 the Stockton & Darlington Railway was under construction as the world's first authorised public railway carrying both freight and passenger traffic. The line's engineer was George Stephenson, who had been appointed in 1821 after the success of his Killingworth engines.

Stephenson formed Robert Stephenson and Company at Newcastle in 1823 to build locomotives for the new railway. Locomotion (originally simply numbered 1) was the first engine built, designed by George Stephenson with his son Robert Stephenson and others at the new works. The design drew on Stephenson's Killingworth experience but with significant refinements: direct connecting-rod drive (no gears), two vertical cylinders set into the boiler for compactness, and proper coupling between the wheels.

The engine was completed in September 1825 and immediately placed in service for the line's opening on 27 September 1825. The opening train consisted of 38 wagons (28 carrying coal, the rest carrying passengers in temporary fittings), with a passenger carriage labelled "Experiment" carrying the railway directors. Stephenson himself drove Locomotion on the opening day. The 12-mile run from Shildon to Stockton-on-Tees took approximately two hours, including stops, and was witnessed by an estimated 40,000 spectators.

Service and withdrawals

Locomotion worked the Stockton & Darlington Railway from 1825 onwards, principally on coal and goods trains. The engine's working life saw the rapid development of British railway technology, by 1830 the Stephenson Rocket of the Rainhill Trials had introduced the multi-tube boiler and demonstrated speeds far beyond Locomotion's capability, and from the early 1830s Locomotion was assigned to lighter work as newer engines arrived.

In April 1828 Locomotion suffered a boiler explosion that killed the driver, John Cree. The engine was rebuilt and returned to service. The engine continued working until 1841, when it was finally retired after 16 years' service.

The Stockton & Darlington Railway recognised the engine's historical significance and preserved it as a static exhibit at North Road station, Darlington, from 1841 onwards. The engine has been preserved continuously since that date, making it one of the longest preserved engines in railway history.

Identification features

A distinctive early-Stephensonian outline. The cylindrical boiler is mounted horizontally, with the two vertical cylinders set into the rear of the boiler, the cylinders project upwards from the boiler casing, with their valve gear visible above. The connecting rods run from the crossheads above the boiler down to the rear coupled wheels. The four wheels are coupled by external rods. A tall vertical chimney rises from the front of the boiler. The whole engine is approximately 14 ft long including the small four-wheeled tender.